Model-based identification and testing of appropriate strategies to minimize NO emissions from biofilm deammonification.

Based on a one-year pilot plant operation of a two-step biofilm nitritation-anammox pilot plant, NO mitigation strategies were identified by applying a newly developed biofilm modeling approach. Due to adapted plant operation, the NO emission could be diminished by 75% (8.8% → 2.

Sinks and sources of anammox bacteria in a wastewater treatment plant - screening with qPCR.

The deammonification process, which includes nitritation and anammox bacteria, is an energy-efficient nitrogen removal process. Starting up an anammox process in a wastewater treatment plant (WWTP) is still widely believed to require external seeding of anammox bacteria. To demonstrate the principle of a non-seeded anammox start-up, anammox bacteria in potential sources must be quantified.

Virus elimination in activated sludge systems: from batch tests to mathematical modeling.

A virus tool based on Activated Sludge Model No. 3 for modeling virus elimination in activated sludge systems was developed and calibrated with the results from laboratory-scale batch tests and from measurements in a municipal wastewater treatment plant (WWTP). The somatic coliphages were used as an indicator for human pathogenic enteric viruses.

Modified ADM1 for modelling an UASB reactor laboratory plant treating starch wastewater and synthetic substrate load tests.

A laboratory plant consisting of two UASB reactors was used for the treatment of industrial wastewater from the wheat starch industry. Several load tests were carried out with starch wastewater and the synthetic substrates glucose, acetate, cellulose, butyrate and propionate to observe the impact of changing loads on gas yield and effluent quality. The measurement data sets were used for calibration and validation of the Anaerobic Digestion Model No.

Nitrous oxide formation during nitritation and nitrification of high-strength wastewater.

The purpose of this study was to investigate the formation of nitrous oxide (N2O) in nitritation and nitrification under stable, comparable and not limiting conditions typical for treatment of high-strength wastewater. A laboratory-scale aerated chemostat was operated with reject water at different sludge retention times, achieving suppression of nitrate formation by wash-out of nitrite-oxidizing bacteria for nitritation. The N2O formation factor during stable nitritation was higher (2.